The present invention relates to a robot system and control method for remote-controlling a robot or controlling a plurality of robots, and a recording medium.
The technology/product field called micromachines has rapidly broadened and advanced along with the advanced micropatterning technique that can form a mechatronics structure on a silicon chip, and miniaturization of peripheral parts. Especially, transportation structures on the .mu.m order have been extensively studied and developed, pushed by the needs for a new medical technique.
Based on changes in social environment represented by growing population of the aged, lower birthrate, a rise of nuclear families, decline of agricultural population, non-popularity of science, and the like, robotization is accelerating its progress not only in the industrial field but also in home use in advanced countries.
Furthermore, owing to population explosion, desertification, agricultural product shortages, energy supply systems, global environmental issues, political instability, and the like, reorganization of unskilled labor propelled by social problems in developing countries has been demanded.
Along with such changes in social structure, one field that has gained widespread appeal is a microrobot having a size around several cm to 100 .mu.m and manufactured by machining/assembly processes. Such microrobot is a relatively large one among micromachines. The microrobot has no clear definition yet, but for those skilled in the art, the microrobot is reckoned to be a robot having a size around several cm, which is manufactured by a mechatronics technique and has a certain level of intelligence, task function, and self-running function, as described in, e.g., Japanese Patent Laid-Open No. 7-168622.
However, those skilled in the art also agree that the size of a similar robot is going to diminish to about several .mu.m and the robot is going to be combined with a biological function due to improvement in machining technique and the like and advance of biological industries. As another technical trend of microrobots, group control is proposed. Microrobots are inferior to human beings and normal industrial robots in most performance fields such as intelligence, transportation capability, speed, task precision, and the like. Merits of microrobots include a scale merit arising from their small size, and lightweight, high safety, low cost, and the like per unit length and unit area on the basis of the small size. To compensate for the demerits and to utilize the merits, attempts to use a group of a large number of microrobots to do a cooperative task, and do tasks such as transportation of heavy articles, display operation, cleaning, and the like have been made.
FIG. 4 shows one example of an existing microrobot control method. In this example, a microrobot detects illuminance differences from the amount of incoming light using a sensor, and travels on a predetermined course.
Referring to FIG. 4, reference numeral 41 denotes a sensor for detecting the light intensity; 42, a microrobot main body; 43, a light source; and 44, a beam spot formed by the light source 43 in FIG. 4.
In this way, a conventional self-running microrobot is controlled by limited processing capability of the microrobot main body and assist means pre-set by an operator.
Hence, it is very hard for such conventional microrobot control method to perform complicated tasks or many, routine tasks.
In particular, the present inventors have developed a microrobot main body to do complicated, difficult tasks (e.g., those listed in (1) to (11) below). However, it is impossible to apply the conventional simple control method to the microrobot, thus interfering with further development.
The conventional control method forms a closed loop in which the operator's instruction (target variable) has a one-to-one correspondence with the state feedback variable. In such control method, for example, when a robot is controlled to do a task at a remote place or in an external environment, the operator's space is physically different from the task space of the microrobot. In such case, it becomes hard to collect information (weather information, local temperature information, and the like) that the operator cannot give and to reflect such information in the control rule.
However, such processing cannot often be done due to the limited processing performance and communication performance of a controller (computer) since a plurality of external conditions must be input to adapt the control rule. Furthermore, in order to independently control a plurality of microrobots, the required computation volume and communication volume increase considerably.
Examples of the complicated, difficult tasks are:
(1) farming tasks such as vermin extermination, weeding, cropdusting, fertilizer sprinkling, watering, sunshine control, measures against bird damage, cultivation, temperature control, reaping, recognition of blight and noxious insects, and the like; PA1 (2) space tasks such as remote sensing, lunar/planetary surface probing, repair of satellite, space dust cleaning, and the like; PA1 (3) energy applications such as solar energy collection, oceanic uranium recovery, solar cell cleaning, nuclear power plant cleaning, and the like; PA1 (4) investigation tasks such as underground resource probing, structure durability inspection, human tracing, oceanic monitor, invasion monitor, police criminal investigation, and the like; PA1 (5) home cleaning such as toilet/bath cleaning, pipe cleaning, vermin control, window cleaning, and the like; PA1 (6) processes for environment protection such as a garbage process, parts recycle process, dangerous article disposal, nitrogen fixing, and the like; PA1 (7) construction/building assistance such as dangerous article inspection, partial painting, small parts transportation, measure against leak in the roof, illumination function, key function, and the like; PA1 (8) factory/distribution assistance such as simplified parts assembly, distribution control, cooperative transportation, and the like; PA1 (9) medical service tasks such as scatoscopy/urinalysis, human waste disposal for sick persons, and the like; PA1 (10) hobby applications such as weekend gardening, pet control, artificial fishing bait, machining assistance, musical instrument performance, automobile cleaning, painting education, and the like; and PA1 (11) safeguard tasks such as lifesaving, patrol task, baggage guard, and the like.